QtPrintSupport - Add CUPS printer and options queries to plugin

Implement initial support in the CUPS plugin for directly calling CUPS
to obtain printer list and basic printer info rather than QCupsSupport.

Add api to the plugin to return any options for a printer, usually IPP
options as implemented for CUPS, but whatever applies for the host
print system.

Future changes will add support for returning the PPD options.  This
api may eventually be added to QPrinterInfo, but not in 5.0.

Change-Id: I6c8bae4c9295009599e6ab31382f5fff4c93981f
Reviewed-by: Teemu Katajisto <teemu.katajisto@digia.com>
Reviewed-by: John Layt <jlayt@kde.org>

4 files changed, 108 insertions, 10 deletions

diff --git a/src/plugins/printsupport/cups/qcupsprintersupport.cpp b/src/plugins/printsupport/cups/qcupsprintersupport.cpp
index 83d4068d16..493e01df5b 100644
--- a/src/plugins/printsupport/cups/qcupsprintersupport.cpp
+++ b/src/plugins/printsupport/cups/qcupsprintersupport.cpp
@@ -46,16 +46,26 @@
 
 #include <QtPrintSupport/QPrinterInfo>
 
-#include "qcups_p.h"
+#include <cups/ppd.h>
+#ifndef QT_LINUXBASE // LSB merges everything into cups.h
+# include <cups/language.h>
+#endif
 
 QT_BEGIN_NAMESPACE
 
-QCupsPrinterSupport::QCupsPrinterSupport() : QPlatformPrinterSupport()
+QCupsPrinterSupport::QCupsPrinterSupport() : QPlatformPrinterSupport(),
+                                             m_cups(QLatin1String("cups"), 2),
+                                             m_cupsPrinters(0),
+                                             m_cupsPrintersCount(0)
 {
+    loadCups();
+    loadCupsPrinters();
 }
 
 QCupsPrinterSupport::~QCupsPrinterSupport()
 {
+    if (cupsFreeDests)
+        cupsFreeDests(m_cupsPrintersCount, m_cupsPrinters);
 }
 
 QPrintEngine *QCupsPrinterSupport::createNativePrintEngine(QPrinter::PrinterMode printerMode)
@@ -74,14 +84,63 @@ QList<QPrinter::PaperSize> QCupsPrinterSupport::supportedPaperSizes(const QPrint
     return QCUPSSupport::getCupsPrinterPaperSizes(printerIndex(printerInfo));
 }
 
-QList<QPrinterInfo> QCupsPrinterSupport::availablePrinters()
+void QCupsPrinterSupport::loadCups()
 {
-    QList<QPrinterInfo> printers;
-    foreach (const QCUPSSupport::Printer &p,  QCUPSSupport::availableUnixPrinters()) {
-        QPrinterInfo printer = createPrinterInfo(p.name, QString(), QString(), QString(), p.isDefault, p.cupsPrinterIndex);
-        printers.append(printer);
+    cupsGetDests = (CupsGetDests) m_cups.resolve("cupsGetDests");
+    cupsFreeDests = (CupsFreeDests) m_cups.resolve("cupsFreeDests");
+    cupsGetOption = (CupsGetOption) m_cups.resolve("cupsGetOption");
+}
+
+void QCupsPrinterSupport::loadCupsPrinters()
+{
+    m_cupsPrintersCount = 0;
+    m_printers.clear();
+
+    if (cupsFreeDests)
+        cupsFreeDests(m_cupsPrintersCount, m_cupsPrinters);
+
+    if (cupsGetDests)
+        m_cupsPrintersCount = cupsGetDests(&m_cupsPrinters);
+
+    for (int i = 0; i < m_cupsPrintersCount; ++i) {
+        QString printerName = QString::fromLocal8Bit(m_cupsPrinters[i].name);
+        if (m_cupsPrinters[i].instance)
+            printerName += QLatin1Char('/') + QString::fromLocal8Bit(m_cupsPrinters[i].instance);
+        QString description = cupsOption(i, "printer-info");
+        QString location = cupsOption(i, "printer-location");
+        QString makeAndModel = cupsOption(i, "printer-make-and-model");
+        QPrinterInfo printer = createPrinterInfo(printerName, description, location, makeAndModel,
+                                                 m_cupsPrinters[i].is_default, i);
+        m_printers.append(printer);
+    }
+}
+
+QString QCupsPrinterSupport::printerOption(const QPrinterInfo &printer, const QString &key) const
+{
+    return cupsOption(printerIndex(printer), key);
+}
+
+QString QCupsPrinterSupport::cupsOption(int i, const QString &key) const
+{
+    QString value;
+    if (i > -1 && i < m_cupsPrintersCount && cupsGetOption)
+        value = cupsGetOption(key.toLocal8Bit(), m_cupsPrinters[i].num_options, m_cupsPrinters[i].options);
+    return value;
+}
+
+PrinterOptions QCupsPrinterSupport::printerOptions(const QPrinterInfo &printer) const
+{
+    PrinterOptions options;
+    int p = printerIndex(printer);
+    if (p <= -1 || p >= m_cupsPrintersCount)
+        return options;
+    int numOptions = m_cupsPrinters[p].num_options;
+    for (int i = 0; i < numOptions; ++i) {
+        QString name = m_cupsPrinters[p].options[i].name;
+        QString value = m_cupsPrinters[p].options[i].value;
+        options.insert(name, value);
     }
-    return printers;
+    return options;
 }
 
 QT_END_NAMESPACE
diff --git a/src/plugins/printsupport/cups/qcupsprintersupport_p.h b/src/plugins/printsupport/cups/qcupsprintersupport_p.h
index 13b65a5cb5..847047226a 100644
--- a/src/plugins/printsupport/cups/qcupsprintersupport_p.h
+++ b/src/plugins/printsupport/cups/qcupsprintersupport_p.h
@@ -44,9 +44,18 @@
 
 #include <qpa/qplatformprintersupport.h>
 
+#include <QtCore/qlibrary.h>
+#include <QtCore/qlist.h>
+
+#include <cups/cups.h>
+
 QT_BEGIN_HEADER
 QT_BEGIN_NAMESPACE
 
+typedef int (*CupsGetDests)(cups_dest_t **dests);
+typedef void (*CupsFreeDests)(int num_dests, cups_dest_t *dests);
+typedef const char* (*CupsGetOption)(const char *name, int num_options, cups_option_t *options);
+
 class QCupsPrinterSupport : public QPlatformPrinterSupport
 {
 public:
@@ -56,10 +65,21 @@ public:
     virtual QPrintEngine *createNativePrintEngine(QPrinter::PrinterMode printerMode);
     virtual QPaintEngine *createPaintEngine(QPrintEngine *printEngine, QPrinter::PrinterMode);
     virtual QList<QPrinter::PaperSize> supportedPaperSizes(const QPrinterInfo &) const;
-
-    virtual QList<QPrinterInfo> availablePrinters();
+    virtual QString printerOption(const QPrinterInfo &printer, const QString &key) const;
+    virtual PrinterOptions printerOptions(const QPrinterInfo &printer) const;
 
 private:
+    void loadCups();
+    void loadCupsPrinters();
+    QString cupsOption(int i, const QString &key) const;
+
+    QLibrary m_cups;
+    cups_dest_t *m_cupsPrinters;
+    int m_cupsPrintersCount;
+
+    CupsGetDests  cupsGetDests;
+    CupsFreeDests cupsFreeDests;
+    CupsGetOption cupsGetOption;
 };
 
 QT_END_NAMESPACE
diff --git a/src/printsupport/kernel/qplatformprintersupport.h b/src/printsupport/kernel/qplatformprintersupport.h
index e922b5fb25..018ec05c03 100644
--- a/src/printsupport/kernel/qplatformprintersupport.h
+++ b/src/printsupport/kernel/qplatformprintersupport.h
@@ -53,6 +53,7 @@
 #include <QtPrintSupport/qprinter.h>
 
 #include <QtCore/qlist.h>
+#include <QtCore/qhash.h>
 
 QT_BEGIN_HEADER
 
@@ -60,6 +61,8 @@ QT_BEGIN_NAMESPACE
 
 #ifndef QT_NO_PRINTER
 
+typedef QHash<QString, QString> PrinterOptions;
+
 class QPrintEngine;
 
 class Q_PRINTSUPPORT_EXPORT QPlatformPrinterSupport
@@ -76,6 +79,9 @@ public:
     virtual QPrinterInfo defaultPrinter();
     virtual QPrinterInfo printerInfo(const QString &printerName);
 
+    virtual QString printerOption(const QPrinterInfo &printer, const QString &key) const;
+    virtual PrinterOptions printerOptions(const QPrinterInfo &printer) const;
+
     static QPrinter::PaperSize convertQSizeFToPaperSize(const QSizeF &sizef);
     static QSizeF convertPaperSizeToQSizeF(QPrinter::PaperSize paperSize);
 
diff --git a/src/printsupport/kernel/qplatformprintersupport_qpa.cpp b/src/printsupport/kernel/qplatformprintersupport_qpa.cpp
index 0a386eafc2..b74a84f9c6 100644
--- a/src/printsupport/kernel/qplatformprintersupport_qpa.cpp
+++ b/src/printsupport/kernel/qplatformprintersupport_qpa.cpp
@@ -107,6 +107,19 @@ QPrinterInfo QPlatformPrinterSupport::printerInfo(const QString &printerName)
     return QPrinterInfo();
 }
 
+QString QPlatformPrinterSupport::printerOption(const QPrinterInfo &printer, const QString &key) const
+{
+    Q_UNUSED(printer)
+    Q_UNUSED(key)
+    return QString();
+}
+
+PrinterOptions QPlatformPrinterSupport::printerOptions(const QPrinterInfo &printer) const
+{
+    Q_UNUSED(printer)
+    return PrinterOptions();
+}
+
 int QPlatformPrinterSupport::printerIndex(const QPrinterInfo &printer)
 {
     return printer.d_func()->index;